Method and apparatus for dispensing gas material



May 5, 1936. w. F. MESINGER v v 2 04 ,05

METHOD AND APPARATUS FOR DISPENSING GAS, MATERIAL Filed June 18, 1935 v3 Sheets-Sheet 1 INVENTOR William ma ORNEYS May 5, 1936.

w. F. MESINGER 2,040,059

METHOD AND APPARATUS FOR DISPENSING GAS MATERIAL Filed June 1a, 1935 3Sheets-Sheet 2 Fig.2;

'81 I 8 I 4 f" Z41 2/8 /22' Q i [2 121' I i 74 g, ,125 14? 1'45 INVENTORATTORNEYS May 5, 1936.

w. F. MESINGER METHOD AND APPARATUS FOR DISPENSING GAS MATERIAL 3Sheets-Sheet 3 Filed June 18, 1955 ml K-IQI INVENTOR Patented May 5,1936 UNITED \STATES PATENT OFFICE DIETHOD AND APPARATUS FOR DISPENS- INGGAS MATERIAL William F. Mesinger, Flushing, N. Y., assignor, by mesneassignments, to Union Carbide and garbon Corporation, a corporation ofNew ork Application June 18, 1935, Serial No. 27,154 19 Claims.(craze-1) This invention relates to a method and apsuch steps withrespect to each of the others, and paratus for dispensing gas materialand per: t apparatus embodying featuresof construc ticularly to a methodand apparatus for dispenstlon, comblnations of elements and arrangementing and transferring liquefied gas to receivers at of Parts Which areadapted to efieot Such p a l relatively high pressure by means of a tranfer asexemplified in the following detailed disclosure,

5 ve el reco ery and condensation of residand the Scope of the inventionbe ual gas. in the claims.

The invention has for its object generally an F a mile! understanding te nature and improved procedure and arrangement of appaoblects of t einvention reference should be had 1O ratus of the character indicatedwhereby aliqueto the following detailed description ke in had gas havingarelatively low boiling point, such eonheetioh with ithe pa y ngdrawings, in as liquid oxygen, liquid nitrogen, and the like, e istransferred to receivers at a relatively high 1 is a View P y in s et'and partly in pressure in an .efiicient and economical mannerelevaftlon showing a fo m of the apparatus a and in which gas providedfor displacing charges cording to the invention wherein the Dlac- 15from the transfer vessel is condensed largely to ing h is temporarilyStored in the gas phase;

liquid and admixed with liquefied gas being trans- 2 is a similar Viewshowing an apparatus ferred whereby blowdown losses are reduced.according to iihe on, having two transfer More specifically it is anobject f the invenvessels arranged for parallel operation together 20 onto provide a methodand apparatus forcari with a modification of thereceiver means for 20 rying the same into effect whereby successivetemporarily storing displacing charges of liquefied gas are passed bymeans of 3 is a e ta y V mainly in ection a single transfer vessel froma transport con-'- shewinge P t of the pp atus modified to tainer whereit is held at a relatively low pressure Provide for h condensation andtemporary storand temperature to receivers at relatively high age of thedisplacing gas in the liquid phas pressure in which the charges areexpelled from 4 is a View mainly in vertical section of the t f vesselby providing a ifi d another form of the apparatus in which chargesliquefied gas having the desired pressure for disf liquefied gas are p iy stored for heat placing the charge. The gas material is conservedexchange With displacing gas bein cooled and 9 by withdrawing thedisplacing gas during the, in-= Partially condensed; and

0 4 terim between charges, temporarily storing and 5 is slmliar eW ofstill another form partially liquefying the same for admixture with ofthe apparatus in which the p a i gas, liquefied gas being transferred.after heat exchange with po arily stored Another object is to providefor the temporary charges f liquefied gas S' t p a y to ed storage f thedisplacing gas in any f several after partial liquefaction for additionto liqueways according to the conditions to be met; one fled beingtransferred rding to the inmethod including the temporary storage of then displacing gas in the gas phase at one or several Heretoifoi'e it hasbeen Proposed to Provide a pressure levels followed by cooling andreconsupply of gas having a at y h pressure 40 densation; a secondmethod including the temat a Piece of use by transporting iiluefled 40po'mry Storage of the displacing gas afte partial in an insulatedcontainer under relatively low liquefaction; and a third including thetemporary pressiire to the Piece of use and there converting storage ofthe displacing gas after partial liquedesired Portion of the liquid intogas at hi h faction by heat exchange with a temporarily Pressure bymeans of v po izing vessel or constored charge of liquefied gas that isbeing trans- Such a V l was supplied with a charge 45 r of llquefled gaswhen at a low pressure and closed;

Still another object is to provide for the conif then heat were eppiieiito the e, it exservation of displacing gas in a system where h nded andb e converted to as having the transfer vessels are operated in parallelby the desired h Pr for passage into the re-' above mentioned methods oftemporary storage ceiveis located t t e place of use. Before re- 50during certain periods of operation. filling such a vessel the gasremaining therein Other objects of the invention will in part be wasreleased to the atmo phere so that liquefied b i u d n in art appearhereinaften gas from the transport container .where it is The inventionaccordingly comprises the sev- 'held at relatively low pressure wouldflow in eral steps and the. relation of one or more of unimpededly. i I55 material due to such blowdown by mechanically compressing the gasreleased to the desired high pressure for use. However, the provision ofa compressor is attended with numerous diiliculties such as providingthe necessary mechanical energy and other complications which aregreatly increased when it is desired to handle gases such as oxygen.

By the present invention theblowdown loss is reduced to an immaterialamount by providing for the temporary storage of displacing gas, itscondensation through heat transfer with liquefled gas being transferredand admixture of the condensed gas with liquefied gas being transferred.To this end, there is provided in addition to a pressure resistanttransfer vessel arranged for receiving charges of liquefied gas from asupply container, a means for providing in the vessel an increased gaspressure which forces a desired portion of the charge to receivers, anda means for conserving a substantial portion of the gas remaining in thetransfer vessel prior to blowdown to the relatively low pressure-desiredwhen recharging, by the withdrawal, temporary storageand partialliquefaction of the gasto be conserved. The liquefaction is achieved bythe utilization of a refrigerating eflect of the liquefled gas beingtransferred.

Referring now to the drawings and particularly to Fig. 1, there is showna vehicle l0 upon which is carried an apparatus for dispending liquefiedgas according to the invention comprising a liquefied gas holding andtransporting container shown generally at A, charge expelling meansshown generally at B and C, and temporary gas storage vessels shown atD. Gas receivers at the place of use shown at E are to be serviced witha supply of. gas under relatively high pressure for consumption upondemand.

The transport container A holds a supply body of liquefied gas ll withina scalable vessel I2, the wall of which is made heavy enough to resistonly moderate pressures and is surrounded by a heat insulating envelopeI3. Customary devices for filling, discharging, indicating pressures andliquid levels, and for releasing gas when the pressure exceeds a desiredlimiting value, are preferably provided in conjunction with container A.Of these only a pressure releasing valve is shown at H communicatingwith container l2 through connection IS; the showing of the others beingomitted in the interest of. clearness of illustration in the drawings.

The transfer vessel B comprises a heavy walled pressure resistant vesselI6 which preferably has within it a relatively thin walled liquidholding vessel or "basket l1 disposed in spaced relation to the innerwall of vessel I Q and supported therefrom by means of interposedspacersof a character that retards the flow of heat across the interval. Forfilling the basket I! of vessel B with a definite or measured charge ofliquid, there are provided separate liquid and gas conduitscommunicating with container l2 at predetermined points, as-shown at I!and i8 respectively. Conduit l8 connects the lower portions of bothcontainer l2 and basket l1 while conduit I! conducts gas from a selectedpoint in the-upper portion of the interior of basket I! which determinesthe level to which filling with liquid is limited, therea,o4o,os9

troduced to the space above the liquid in vessel IS. A preferred meansfor accomplishing this is shown at C in the form of a so-called thermalleg in which a heating element 20 is arranged to receive heat from aheating medium in a jacket 2| and heat and vaporize the gas material ata rapid rate and raise the same to a relatively high temperature. Thelower portion of element 20 is placed in communication with the. liquidin basket IT at a. point below the normal liquid level by means ofconduit 22 controlled by a valve 22' that is normally open, while theupper portion of element 20 communicates with the space above the liquidlevel through a conduit 23 which has a control valve 23' that isnormally open.

Valves I 8' and lfl'controlling conduits l8 and I9 respectively are alsoprovided.

The charge in basket i1 is expelled to the receivers through a conduit24 which leads from' the bottom of the basket and is controlled by valve24'. This conduit may, when desired, conduct the gas material directlyinto receivers according to the invention. However, in the form hereshown, the conduit 24 is provided with two portions in which heat isimparted to the gas material discharged. One of these portionscomprising a pipe coil 25 is heated by a heat storage material 26 whichis disposed in contact therewith. The heat storage material andassociated support is hereinafter termed a regenerator. and is generallyindicated at R. Such material may be of any suitable substance havingthe' desired heat storage capacity; for example, a body of cast metal ora mixture of mineral salts or a fluid in which the coils are embedded.The second heat receiving portion of conduit 24 is shown in the form ofan extended portion at 21 disposed to be enveloped in the heating mediumin jacket 2| and is termed a heater, since it receives and heats the gasmaterial and discharges the same at the temperature desired. The heater2'! has an exit connection 28 which is connected by means of a coupling29 to a service conduit or distributing manifold 30. Connection 28 iscontrolled by a stop valve 28 and I a check valve 3|, while manifold 30is controlled by stop valve 30'. onetor more receivers 32 are connectedto the manifold 30 to receive the discharge, the connection beingpreferably made through flexible connections 33.

The temporary gas storage means D may consist of one or more pressureresistant gas receiving vessels or containers, a plurality being shown,

and each being provided with an individually controlled inlet forholding gas at a corresponding number of diiferent pressure levelsaccording to the degree of efliciency in conserving gas desired. 'Heresuch containers are shown respectively at 34, 35 and 36, and haveconnections to a manifold 31, which are controlled respectively byvalves 38, 39 and 40. The manifold 31 communicates with the interior ofvessel It.

through two passages, the one formed by connection 4| which iscontrolled by valve H for passing gas from the vessel It to thecontainers D, the other passage being formed by a conduit 42 which has acoiled portion 43 in thermal contact with regenerator material 26 forimparting heat thereto. The conduit 42 conducts gas from manifold 31through coiled portion 43 to a distributor 44 which is disposed in thelower portion of the liquid holding space of basket I1. Flow throughconduit 42 is limited in direction tolthat toward vessel I 8 bymeans ofa check va ve 45 which is also arranged to provide a Y in heatinsulating material. The normal flow of gas material through itspassages is" preferably in countercurrent directions when a temperaturegradient is preferably maintained from one end to the other.

The size of the .transfer vessel B is determined by selecting themaximum amount of liquid charge that it is desired to transfer at onetime. This may be so small that it would fill only one receiver 32 or itmay be larger where more than one receiver is to be filled by thetransfer of one or more charges, depending on the conditions to be met.The capacities of the several containers 34, 35 and 36 need not be thesame, andfor the lower pressures containers may be relatively large.

In the operation of servicing a consumers receivers E with liquefied gasusing this apparatus, the container A is filled with liquefied gas at agas liquefying and producing plant, transported to the place of use andthe connection 29 coupled to manifold 39. All the valves are assumed tobe closed except those of receivers 32. The basket I1 is filled to thedesired level with a charge of liquefied gas by opening valves l9 and I9so that the liquid flows over under'the influence of gravity while thegas displaced or vaporized during the filling flows into containerl2'wherein the pressure is increased. Should the pressure in containerl2 rise to the desired limiting value, further input of gas will causethe relief valve 14 to open and release gas to the atmosphere.vaporization of liquid entering vessel I 9 caused by heat inflowtransferred from the walls of the vessel I6 is held to an incensequential amount by virtue of the insulating effect of the space intervalabout the basket l1.

The predetermined charge is next expelled from vessel B by closingvalves l9 and I9" and opening valves 24, 29', 39', 22 and 23. Thermalleg immediately receives some liquefied gas through connection 22, heatsit to a relatively high temperature and discharges the resulting warmgas into the space above the liquid level and builds pressure thereinrapidly to a value exceeding that in receivers 32. The thermal leg actsin accordance with the principles described in copending application,Serial 'No.-

3,249, filed in the name of G. 1-1". Zenner. The major portion of thecharge is forced out through conduit 24 reaching finally the receivers32. In

passing through coils 25 the refrigeration or heat absorbing power ofthe gas material extracts heat from the regenerator 26 and cools it to arelatively low temperature. The gas-material discharged is finallyheated to desired temperature when passing through heater 21.

The vessel B, after expulsion of the charge,

contains displacing gas of relatively high temperature and pressureapplied by the thermal leg C, which gas is withdrawn from vessel B inorder that it may be recharged. To accomplish this and at the same timeconserve a substantial amount of the displacing gas, portions of gas arepassed to the storage containers D. Since in this case there are threesuch containers, the passage is eifected in three steps as follows: Withvalves 22', 23' and 24' closed, valves 39 and ll are opened and gas willpass from vessel B to container 34 until the pressures equalize. Valve38 is next closed and valve 39 opened until the pressures of vessel Band container 35 equalize at a lower value. Finally valve 39 is closedand valve 4!! opened and equalization of pressures between vessel B andcontainer 39 takes place at a still lower value, after which valves 49and 4| are closed. I

.While the displacing gas is temporarily stored in containers D, vesselB is recharged as before with liquid from container A and when socharged valves l8 and I9 are closed and valve 49 opened.

Gas now flows from container 39 through manifold 31 and conduit 42 andinto vessel B where it is introduced into the liquid charge bydistributor 44. On passing through coil portion 43, the displacing gasimparts heat to the regenerator 26, being cooled thereby so that it maymore readily be condensed: Refrigeration contained in the charge thatwas expelled is thus usefully transferred to the displacing gas which isbeing condensed On issuing from distributor 44 the cooled gas mixes withthe charge which is at first at a relatively low temperature andpressure and is partially condensed. In consequence both the temperatureand pressure of the charge rise a relatively small degree and thepressure of gas in container 36 is reduced a desired amount. In similarmanner containers 35 and 34 are dis- I charged successively to vessel Bby closing valve 40, opening valve 39, then closing valve 39 and openingvalve 38 which is closed after the pressures of container and vessel Bequalize. On passing check valve 45, which is constructed to provide athrottling action on the gas flowing toward vessel B, the gas is furthercooled by the Joule-Thompson effect'caused by the throttling action whenthe pressure differences are great enough. I

The charge, now augmented by the displacing gas that was added to it, isexpelled to the receivers bythe action of the thermal leg C as explainedin connection with the expulsion of the previous charge. The cycle ofexpulsion, displacing gas storage, charging, and displacing gas Afterthe final charge required for filling the receivers E has been expelledfrom vessel B, the displacing gas is preferably stored in containers Dand vessel B and transported with the apparatus 'to another place of usewhere it may be added to the first charge to be expelled to another setof receivers.

The step of precooling by regenerator action the displacing gas to becondensed is not an essential element of the invention and may beomitted where it is desired not to heat gas material being expelled fromvessel B. Omission of the regenerator where discharge is to be stored asa medium pressure liquid is not an advantage. The same energy must betransferred to the liquid from the residual gas or must be blown to theatmosphere. Use of ,a regenerator would permit lower equalizationpressures and consequent lower losses',lwithout appreciably changingthetemperature of the liquid discharge to the storage would not be usedwhen the liquefied gas is to' beexpelled into an insulated receiver forstorage therein at a relatively low temperature and moderately elevatedpressure. In such' a case, the discharge ,conduit 24 would be modifiedto connect directly .to the receiver and heat receiving portions 25 and21 omitted. The displacing gas is then fed directly into the liquidcharge and cooled and partially condensed thereby.

When eflicient recovering of displacing gas according to the presentinvention is practiced, it

.is economically feasible to transfer a desired two or more transfervessels may be operated in parallel. Hence, in any of the forms of thepresent invention described, it is contemplated that parallel systemsmay be operated and that certain portions of the apparatus maybe commonto both systems. For example, in each of the forms illustrated in theseveral figures of the drawings, the transfer vessel B may be providedin duplicate with conduits and control valves arranged so that theymaybe operated in parallel to be alternately charged from the common supplycontainer and alternately discharged by a common thermal leg Cfurnishing the displacing gas. The means for temporarily holding and/orcondensing displacing gas may also be common to both transfer vessel 7Referring now to Fig. 2, there is shown a modifled form of apparatus inwhich two transfer vessels B and B" are provided and the receivers at Eare arranged to function also as containers for temporarily storingdisplacing gas to hold the same until a fresh charge is available forequalization.- The containers D are omitted and the displacing gas ispassed to a selected consumers receiver by means of conduit 41 whichconducts the gas from vessels B and B" to an auxiliary manifold 48. Eachof the receivers 50, 52, etc.

is connected to each of the manifolds by connections controlledrespectively by valves 53, 53, 54, 54, 55, 55'; admission of gas frommanifold 30 to cylinders 50, 5I, 52 being controlled by the group ofvalves 53, 54, 55, while that from manifold 45 is controlled by thegroup of valves 53, 54',

55'. The receivers 50, 5 I, etc. may consist each of a single cylinderor of interconnected groups of cylinders whichare charged as a unit.

In this form of the apparatus, the transport container A is notsufilciently elevated with respect to the'transfer vessels Band B" toallow gravity flow of liquid at all times when charging.

Transfer of liquid is therefore effected by providing a superatmosphericpressure on the liquid in container A to force liquid under theinfluence of difference of pressure through the transfer conduit Ilainto either of the transfer vessels. Conduit I la is connected to bothvessels H5 and 2I5 by connections H8 and 2I5 respectively. The transfervessels are vented when desired through connections H9 and 2I9 whichleadgas from the upper portions of vessels IIS and 2I8 respectively.

The discharge conduit 24 is provided with two branches I24 and 224leading from the lowermost portions of vessels I I5 and H5 and alsohasinterposed a pass I25 of the regenerator R. The other pass I43 of theregenerator is interposed in the conduit I42 which conducts gas frommanifold into the transfer vessels. The conduit I42 has branches I and 2which conduct the gas through the vessel walls to the diffusers I44 and244 which are disposed in the lower portions of vessels I I5 and 2I6respectively. The conduit 41 joins conduits I and 2H attheir Junctionwith densed by the liquid in vessel II6.

conduit I42. Operative connection of the ves- Valves for controlling theconduits are pro-- vided. Thus, valves 8'; 2I3', II9', 2I9', I24, 224',Hi, I42, 24I' control the conduits II8, 2I3, II9, 2I9, I 24, v224, I4I,I42, 2, respectively. Check valves are provided in conduits 41 and I42;in the former, the check valve 49 for permitting flow only in thedirection toward manifold 48, and in the latter. check valve I45 forallowing flow to take place only away from manifold 45.

In operation, the two transfer vessels are alternately charged, forexample, vessel H5 is charged by opening valves I I8 and 9' for thedesired period, the displaced gas being vented through connection II9 tothe atmosphere to provide the required pressure difference for the flowof liquid. Valves H8 and II 3' are-closed after vessel IIG has beenproperly filled. Gas is now drawn from the receivers which are selectedfor temporary storage of displacing gas, for example, from receiver 52by opening valves 55', I42 and I 4.I' to permit gas to flow fromreceiver 52 through the conduits 48, I42 and I to diffuser I44 where thegas is mixed with and partially con- Gas may similarly be removed fromreceiver 5I by closing valve 55 and opening valve 54' untilthe pressuresequalize, after which the valves are closed.

Thermal leg C is next connected to vessel II6 by opening valves I22 andI23 to build the pres sure to the desired value and valves I24, 35' and53 are opened to permit discharge toward the receiver 55 through thesystem of conduits I24, 24, I25, 21, 28, 30 and connection controlled byvalve 53. During this discharge, the vessel 2I5 is filled by openingvalves 2I8' and 2I3' for the proper interval.

' When the flow of gas material out of vessel I I6 substantially stopsvalves I22, I 23' and I24 are closed and valves HI and 54' opened sothat gas flows from vessel 6 into receiver 5I through connection 41 andcheck valve 49 until the pressures equalize. Similarly, the pressures ofvessel H6 and receiver 52 are equalized at a lower value by closingvalve 54' and opening valve 55' for the desired period. If desired, across-equalization'between vessels H5 and 2I5 may be practiced at thistime to still further reduce the amount of displacing gas remaining invessel I I5. This is accomplished by closing valve I42 and opening valve2,.4I' (valve'I4I' being open). Some gas will thereupon fiow from vesselII5 into the fresh charge of liquid in vessel 2I5 through the systemI44,, I4I, 24I, 244. Valve MI is closed and charging of vessel H5 is nowstarted while gas temporarily stored in receivers 52 and 5| is caused toflow to vessel 2I5 by opening individually and successively for thedesired period the valves 55' and 54' events is repeated until thereceiver system represented by receiver 50 is charged with gas to thedesired pressure. "When' this occurs, valve 53 is closed and valve 54 isopened, so. that receiver 5I may be charged to the desired pressurewhile other receivers are selected to provide 'for thetemporary storageof displacing gas.

In the form of apparatus shown in Fig; 3, the function of temporarystorage of displacing gas is provided, not by containers for holdingthis gas respectively. The cycle of' I sels H6 and 2I6 with the thermalleg C is had by 'of the regenerator generally indicated at R. The

regenerator R comprises a pressure resistant shell 59 within which isdisposed the multi-tubular pass 58 whose tubes-terminate in lower headerchamber 60 and upper header chamber 8|. Conduit24 connects with lowerheader 60 after passing through a joint sealing packing 62 in the lowerend of shell 59. The heater 21 has a conduit connected with the chamberSI for conducting the gas from the regenerator into the heater. Theshell contains heat storage or regenerator material 63 of suitable form,such as a series of baiiies disposed about the tubes of pass 58. Theshell 59 is sufilciently large to provide a substantial space within andabout the tubes 58 to afford temporary storage of cooled and partiallyliquefied displacement gas. For conducting displacing gas into the shellthere is provided a'conduit 54 leading from distributor 44, through thewall of vessel I6 to the upper part of the interior of shell 59 whichconduit is controlled-by valve 64'. The displacing gas is dischargedfrom the shell 59 through connection 65 controlled by valve 65,which-connects the lower portion of the shell 59 with conduit 64 at apoint between the valve BQ'T and vessel I6.

When dispensing gas material with this modification of the apparatus,vessel B, having been charged with a predetermined amount of liquefiedgas as described in connection with Fig. l, is discharged by opening thevalves 22' and 23' for placing thermal leg 20 in communication with thevessel. When valves 24 and 28' are opened, the charge is expelled andfiows to the receivers at E through conduit 24, tubular pass 58 ofregenerator R, heater 2! and manifold 30. In the regenerator, heat isabstracted from and refrigeration trasferred to the heat storagematerial 63 and associated metal parts such as the surrounding metalwalls of chamber 60 and tubes 58 which are cooled to a relatively lowtemperature. Since the gas material is warmed on its passage through theinner pass 58, the end of the regenerator adjacent chamber GI will notbe cooled to so great a degree as the end adjacent the chamber 60.

When the desired amount of charge has been expelled, valves 22', 23 and24 are closed, and

displacing gas is passed into the regenerator by opening valve 64. Thisgas flows through distributor 44, conduit 64 and through the passagesbetween bafiles 63 and arounclwthe tube 58 toward the lower end ofregenerator R. stracted from the displacing gas by the cold regeneratormaterial to a degree which causes partial liquefaction and a largereduction of the pressure of the displacing gas .with'the result thatthe mass of displacing gas remaining in vessel -B is reduced to adesired small amount.

The portion of the displacing gas that is 1ique-' fied collects in thelower portion of the regenerator adjacent the chamber 60. Valve 64 isclosed to temporarily hold displacing gas in the regenerator R whilevessel B is recharged. If it is desired not to increase the pressure ofgas in the transport container, the valve II may be Heat is abopened fora suflicient time for releasing gas, for example, to the atmosphere,after which the vesseYB may be recharged by opening valves I8 and I9.After charging is completed and valves IB'," I9 are closed, valve 65 isopened so that displacing gas conserved will return to vessel 3- and mixwith the charge therein. The flow occurs from the colder lower end ofregenerator R through conduit 55 and part of conduit 64 to distributor44 so that a further amount of displacing gas is condensed by the freshcharge and the pressure of gas in the regenerator reduced to asubstantially lower value. This pressure is further reduced when theregenerator is cooled by the passage of the charge of liquid in vessel Bwhich is next expelled. Then valve 65' isclosed, valves 22', 23' and 24'are opened and the charge is expelled by heated displacing gas. Theexpelled charge which fiows through the pass 58 .cools the regeneratormaterial 63 as before deincreased ability for receiving the followingcharge of displacing gas.

In the form of' apparatus of Fig. 4, the con-- densation of displacinggas is provided for by a temporary storage of a charge of liquefied gasafter it is expelled from the vessel B, which again may comprise aheavy-walled chamber I8 having a basket IT. The vessel B and theexpelling device or. thermal leg C are of similar form to that alreadydescribed. However, the vessel B is not filled with liquid by gravityfiow, but the liquid charge is displaced from transport container I2into the transfer vessel by means of a difference of pressure throughconduit H8 controlled by valve 8'. This conduit .leads from a point inthe lower part of the liquid body I I into theupper part of vessel B.For releasing gas and determining the desired filling level the conduitI lI controlled by valve Ill is provided, passing through the upper partof vessel B, and hasits internal opening at the. desired liquid level.The liquid is discharged from vessel B through conduit 64 which conductsit from the lower part of basket I! into a high pressure charge storagevessel 66, which preferably is provided with an inner lining vessel orbasket 66'. Disposed within the basket is heat exchange means in theform of a coiled pipe 61 which has an inlet portion I58 controlled byvalve 68' connected with conduit 54 and an outlet portion 69 passingthrough 'the' lower part of vessel 66 and conducting to an expansionvalve Ill whose discharge 1I enters the upper portion of vessel I2. Thedischarge conductor II is arranged to diflfuse the gas discharged fromvalve I0 into the gas space above the liquid in container gas dischargedto consuming devices E that may include a heater, when desired. Aby-pass connection l4 controlled by valve 14' is also provided betweenconduit 54 and conduit 12 joining the latter between check valve 13 andcoupling I29. The conduit 54 is controlled by valve 64 at a pointadjacent vessel 65. v

In operating this form of apparatus, vessel B is filled with apredetermined charge of liquid by opening valves I I8 and I4 I so thatthe escape of gas at conduit I lI reduces the pressure in vessel B belowthat in container A and liquid is displaced through conduit II8 untilthe liquid level in basket I'I rises to the opening of conduit Ill.

, Then valves I I8 and Ill are closed and thermal expansion valve 10,which is set at the desired opening to provide a throttling of the gasmaterialpassing, and into container I 2. On its passage through coil 61the displacing gas is cooled to a relatively low temperature andpartially liquefied, and when passing through throttle valve 10, thegasis further cooled and liquefied. In the diffuser H a separation ofliquid and gas phases takes place, the liquid portion dropping to joinwith the body of liquid so that it mingles with liquefied gas beingtransferred, and the gaseous portion assists in building up the pressurein container A up to the value at which the releasing valve is setto'act.

Vessel B is refilled with another charge and the charge expelled in thesame way as described.

The second charge, however, displaces the first stored charge fromvessel 68 through conduit 12 to the receivers E. The by-pass valve II isopened when it is desired to avoid'adding to vessel 66, gas dischargedfrom vessel B which is of too high a temperature to augment thecondensing capacity of the material in vessel 66. The by-' passing isaccomplished toward the end of the expelling period by opening valve 14'and closing valve 64.

The modification of apparatus shown in Fig. provides for storage of thedisplacing gas in the partially liquefied state-as well as for temporarystorage of an expelled charge. The vessel B is shown as arranged forfilling by gravity from 'con-- tainer A, as in Fig. 1, and its charge isexpelled by means of a thermal leg device C shown enclosed in itsheating jacket. The vessel 68 is shown located above the thermal leg,which is a convenient location but is adapted mainly in the interests ofclearness of thedrawings. The charge is expelled from vessel B throughconduit II which conducts gas material from a point near the bottom ofthe basket to conduit 64 which it Joins. Conduit 84, when its controlvalve 64' is open, conducts the gas material into vessel 66 at anintermediate point, where it passes through the wall of the basket 66'into a. ring form dlflus-"f ing passage 11 that is provided withnumerous heat exchange coil inwardly opening passages. endedthin metalbaflle I8 is basket 66' in such a manner A cylindrical open disposedwithin the 81 and be spaced uniformly away from the wall of the basket,whereby a circulation passage is provided. The coil inlet connection 68also connects to and communicates with the conduit 16 for withdrawingdisplacing gas. The outlet connection 89 of thecoil 81 conducts cooleddisplacing gas to the expansion or throttle valvelll' and its diffuser Hwhich is here arranged to discharge into an auxiliary storage chamber80. The chamber 80 is constructed to withstand a desired intermediatepressure and is preferably heat insulated as well as vessels It and 66and container A. Chamber .0 is provided with a relief valve 8| and adischarge connection 82 controlled by a valve 82. for providinscommunication between the lower portion of chamber 80 and the conduit16. A 00111311111108.51- ing passage from chamber 80 into vessel A maybe also provided when desired. The discharge conduit 12 of vessel 66 isshown passing through a separate heater jacket 83 wherein it is providedwith an extended portion and finally joining coupling 29 to whichreceiving devices are coupled.

The operation of this form of apparatus is similar to thatdescribed inreference to Fig. 4 with slight modification. The vessel B is chargedand its charge expelled as before described. Since the gas materialflowing into vessel 66 through conduit 64 is colder at the start of theexpulsion period than at the end, it is desirable that the colder gasmaterial settle to the lower portion of the basket 66 and the warmer gasmaterial collect at the upper portion of vessel 66 from which it isdischarged. This separation is effected by the action of the diffuser11, which reduces the turbulence created by the infiowing gas, and bythe baflle 18 which allows the warmer gas to circulate upward withoutturbulence. When expulsion is completed to the desired degree and valves22', 23 and 64are closed, valves 68' and are opened, the first fully,and the latter partially to provide a throttling action. The displacinggas thereupon flows from vessel B, through coil 81 where it is cooled bythe stored gas material surrounding the coil, and into chamber 80 in apartially or completely liquefied state. The relief valve 8| is adjustedto release gas when a certain pressure in chamber 80 is exceeded,

, which pressure is generally selected to .provide a maximum recovery ofdisplacing gas. When displacing gas stops flowing, valve 6 8' is closedand vessel 13 is recharged with liquefied gas. When basket I1 is filledto the desired level, valves' l8- and' I9 are closed and valve 82'opened, whereupon displacing gas conserved in chamber 80 fiows intoand'is mixed with the charge in basket l1. when the pressures equalizethe valve 82' is closed and valves 22', 28' and 64' are opened v toexpel th kgharge, which on entering vessel 66 displaces the warmer gasfrom the upper portion thereof to the receiving apparatus at E.

With the forms of apparatus shown in Figs. 4 and 5, it will be seen thatthere is provided a method of conserving the displacing gas, after thefinal charge of liquefied gas has been expelled.

It is contemplated also that still more effective conservation ofdisplacing gas may be obtained by a combination of the method oftemporarily storing portions of the displacing gas in-the gas phase aspracticed when using the apparatus of Figs. 1 and 2, with the method oftemporarily storing displacinggas in the liquid phase according to thearrangements 'in Figs. 3 and 5, and

' with the method of temporarily storing the charge as to surround theexpelled for purpose of heat exchange according to Figs. 4 and 5.

Since certain changes in carrying out the above process. and in theconstructions set forth, which embody the invention may be made withoutdeparting from its scope, it is intended that all matter contained inthe above description or shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense. I a

Having described nrv invention, what I claim as new and desire to secureby Letters Patent is:

1. A method of transferring a liquefied gas that is volatile at normalatmospheric pressure from a supply vessel where it is held at relativelylow pressure and temperature to receivers at relasubstantial portion ofthe gas remaining-in the transfer vessel after the desired amount of theliquefield gas charge has been expelled to receivers, releasing gas fromsaid transfer vessel for 4 reducing its pressure .to the relatively lowvalue desired for refilling, and utilizing a refrigeration 'effect ofthe liquefied gas being transferred for recondensing a substantialportion of said withdrawn gas. J

2. A method of transferring a liquefied gas that has a gas phase evolveddue to heat gained in the transfer from a supply source where it is heldat a relatively low pressure to a receiver at a relatively high pressureby the employment of a transfer vessel, which comprises transporting abody of liquefied gas held at a low pressure and temperature to adestination, segregating a measured portion of liquefied gas in atransfer vessel leaving a desired gas space therein, increasing thepressure of gas in said gas space to a relatively high value, expellingunder the action of said pressure a desired portion ofsegregated'liquefied gas to a receiver, withdrawing gas from saidtransfer vessel, displacing additional gas from said transfer vesselwhen refilling with another measured portion of liquefied gas, andcooling and recondensing said withdrawn gas by thermal contact withliquefied gas being transferred whereby loss of such material in the gasphase is reduced.

3. A method of transferring a liquefied gas that has a gas phase evolveddue to heat gained in the transfer, from a supply source where it isheld at a relatively low pressure toa receiver at a relatively highpressure by the employment of a transfer vessel, which comprises passinga substantial portion of the gaseous residue of a previous operationleft in the transfer vessel under pressure into temporary storagecontainers, reducing the pressure of gas in said transfer vessel to arelatively low value, displacing gas from said transfer vessel with ametered charge of liquid drawn from said supply source, liquefying amajor portion of the gas passed to temporary storage containers by heatexchange with volatile liquid being transferred, admixing the gas soliquefied with other volatile liquid being transferred whereby the lossof gas by blowdown of the transfer vessel is reduced, and expelling adesired portion of said metered charge from the transfer vessel to saidreceiver by the application of heat.

4. A method of transferring a liquefied gas that has a gas phase.evolved due to heat gained in the transfer, from a supply source whereit is held at a relatively low pressure to a receiver at a relativelyhigh pressure by the employing of a transfer vessel, which comprisesisolating a metered charge of liquefied gas in said transfer vessel intowhich it has been introduced under a relatively low pressure, raisingthe pressure environment of said charge to a value exceeding saidrelatively high pressure by flowing a portion of the charge through aheated region for heating and vaporizing the same while maintaining thebalance of said charge substantially unheated, discharging a desiredportion of said charge to said receiver leaving a gas phase remainder insaid transfer vessel, passing a substantial portion of said remainderintotemporary holding means, cooling and partially recondensing saidportion of re-' mainder by means of the refrigerating effect ofliquefied gas being transferred, and admixing said cooled and partiallycondensed portion with volatile liquid being transferred.

5. A methodof transferring a liquefied gas that has a gas phase evolveddue to heat gained in the transfer, from a supply source where it isheld at a relatively low pressure to a receiver. at a relatively .highpressure by the employment of a transfer vessel, which comprises-passinga metered charge from the supply vessel into the transfer vessel when atits lowestpressure, isolating said charge from communication with thesupply vessel, supplying regasified liquefied gas having a relativelyhigh temperature into the transfer vessel above the normal liquid leveltherein until the pressure acting on said charge exceeds the pressure ofmaterial in the receiver, discharging a desired portion of said chargeto the receiver leaving a gas phase remainder in said transfer vesselhaving a relatively high pressure, preparing said transfer vessel forreception of another charge by first withdrawing a substantial portionof said remainderto temporary holding means and secondly releasing gasfrom said vessel until said lowest pressure is substantially reached,and thereupon cooling, partially recondensing and admixing saidwithdrawn remainder with liquefied gas being transferred. i

6. A method of. transferring a liquefied gas that has a gas phaseevolved due to heat gained in the transfer, from a supply source whereit ,is held at a relatively low pressure to a receiver of the gasdisplaced from said transfer vessel by each charge by withdrawingsaid-portions, and

partially liquefying and admixing said portions with liquefied gas beingtransfered.

- 7. A method of transferring a liquefied gas that has a gas phaseevolved due to heat gained in the transfer. froma supply source where itis held at a relatively low pressure to a receiver at a relatively highpressure by the employment of a transfer vessel, which comprisesinterposing a transfer vessel between said container and receiver',delivering a metered charge from said container into said transfervessel, discharging the liquid contents of said transfer vessel to saidreceiver through displacement by gas provided by heating a portion ofsaid charge, withdrawing and condensing at least a portion of thedisplacing gas during the interim between dis- ,charges, and adding thecondensate to volatile liquid being transferred.

8. A method of transferring a liquefied gas that has a gas phase evolveddue to heat gained in the transfer, fro-m a supply source where it isheld at a relatively low pressure to a receiver at a relatively highpressure by the employment of a transfer vessel, which comprisestransferring successive charges of liquefied gas to said transfer vesselate. relatively low pressure, expelling each charge from said vessel toreceivers by displacement with gas of relatively high temperature andpressure, withdrawing displacement gas after it has effected -thedesired expulsion, temporarily storing withdrawn displacement gas, andpartially liquefying and admixing displacement gas with liquefied gasbeing transferred whereby to,

conserve gas material.

9. A method of. transferring a liquefied gas that has a gas phaseevolved due to heat gained in the transfer, from a supply source whereit is held at a relatively low pressure to a receiver at a relativelyhigh pressure by the employment of a transfer vessel; which comprisestransferring successive charges of liquefied gas into said transfervessel at a relatively low pressure, expelling each charge from saidvessel to receivers by displacement with gas of relatively hightemperature and pressure, withdrawing displacement gas after it haseffected the desired expulsion, temporarily storing displacement gas ata plurality of successively lower pressure levels, and partiallyliquefying and admixing stored displacement gas with liquefied gas beingtransferred, said admixing being effected at successively higherpressure levels.

10. 'A method of transferring a liquefied gas that has a gas phaseevolved due to heat gained in the transfer, from a supply source whereit is held at a relatively low pressure to a receiver at a'relativelyhigh pressure by the employment of a transfer vessel, which comprisestransferring successive charges of. liquefied gas into said transfervessel at a relatively low pressure, expelling each charge from saidvessel to.receivers by displacement with gas of relatively hightemperature and presure, withdrawing displacement gas after it haseffected the desired expulsion, cooling said displacement gas by meansof a refrigerating effect of gas material expelled from the transfervessel, and partially liquefying and.

admixing displacement gas with liquefied gas being transferred wherebylosses of gas by blowdown are immaterial in amount;

11. A method of transferring a liquefied gas that has a gas phaseevolved due to heat gained in the transfer from a supply source where itis held at a relatively low pressure to a receiver at a relatively highpressure by the employment of a transfer vessel, which comprisestransferring successive charges of liquefied gas into said transfervessel at a relatively low pressure, expelling each charge from saidvessel to receivers by displacement with gas of relatively hightemperature and pressure, withdrawing displacement gas after liquefiedgas being it has effected the desired expulsion, cooling and partiallycondensing the withdrawn displacement gas by utilizing a refrigeratingeffect of gas material expelled from the transfer vessel, temporarllystoring the partially condensed dis.- placement gas during the interimof charging the transfer vessel, portion of the displacement gas withcharges of transferred.

12. A method of transferring a liquefied gas that has a gas phaseevolved due to heat gained in the transfer, from a supply source whereit is held at a relatively low pressure to a receiver at a relativelyhigh pressure by the employment of a transfer-vessel, which comprisescooling the withdrawn displacement gas by heat exchange with gasmaterial having a refrigerating effect expelled from the transfervessel, further cooling and partially liquefying the withdrawn disfieddisplacement gas with the other liquefied has effected said expulsion,

and admixing a substantial 13, Apparatus for dispensing "gas materialcomprising the combination with a heat insulated container for holding acharge of liquefied gas at relatively low pressure, of a heat insulatedpres-' sure resistant transfer vessel arranged to receive portions ofsaid charge and to expel gas material at a desired relatively highpressure, means for receiving the gas material expelled, and means fortemporarily holding and recondensing gas withdrawn from said transfervessel after the desired amount of gas material has been expelled to thereceivers. i

14. Apparatus for dispensing gas material comprising the combinationwith a heat insulated containe'rfor holding a charge of liquefied gas atrelatively low pressure, of a receiver for receiving gas material at arelatively high pressure, a transfer vessel interposed between thecontainer and the receiver arranged to receive successive portions ofsaid charge when at low pressureand to expelgas material to saidreceiver at relatively high pressure, means for providing gas to effectsuch expulsion by displacement, means for withdrawing and temporarilystoring 'displacement gas after it has effected said expulsion, andmeans for partially liquefying and admixing displacement gas withliquefied gas.

15. Apparatus for dispensing gas material comprising the combinationwith a heat insulated container for holding a charge of liquefied gas atrelatively low pressure, of a receiver for receiving gas material at arelatively high pressure, a transfer vessel interposed between thecontainer and the successive portions of said charge when at lowpressure and to expel gas material to said re ceiver at relatively highpressure, means for providing gas to effect such expulsion bydisplacement comprising athermal leg communicating =-with the transfervessel at points above and below receiver arranged to receive rarilystoring displacement gas material after it and means for admixingdisplacement gas material with liquefied gas.

; ,l6. Apparatus for dispensing gas material comprising the combinationwith a heat insulated container for holding a charge of liquefied gas atrelatively low pressure, of a receiver for receiving gas material at arelatively high pressure, a transfer vessel interposed between thecontainer and the receiver arranged to receive successive portions ofsaid charge when at low pressure and to expel gas material to saidreceiver at relatively high pressure, means for providing gas to effectsuch expulsion by displacement, means for withdrawing and temporarilystoring at a' plurality of successively lower pressures displacement gasafter it has effected said expulsion, and means for admixing atsuccessively higher pressures temporarily stored displacement gas withliquefled gas being transferred.

17. Apparatus for dispensing gas material comprising the combinationwith a heat insulated container for holding a charge of liquefied gas atrelatively low pressure, of a receiver for receiving gas material at arelatively high pressure, a transfer vessel interposed between thecontainer and the successive portions receiver arranged to receive ofsaid charge when at low viding gas to effect such expulsion bydisplaceexpelled from after it has eilected said expulsion. means forcooling the withdrawn displacement gas by utilizing a refrigeratingeffect of gas material the transfer vessel, and means for admixingcooled displacement gas with liquefied gas being transferred.

18. Apparatus for dispensing. gas material comprising the combinationwith a heat insulated container for holding a charge of liquefied gas atrelatively low pressure, of a receiver for receiving gas material at arelatively high pressure. a transfer vessel interposed between thecontainer and the'receiver arranged to receive successive portions ofsaid charge when at low pressure and to expel gas material to saidreceiver at relatively high pressure, means for providing gas to effectsuch expulsion by displacement, means for withdrawing displacement gasafter it has eflected said expulsion, means for cooling the withdrawndisplacement gas by utilizing a refrigerating effect of gas materialexpelled from the transfer vessel and for storing the same in apartially liquefied state, and means for admixing partially liquefieddisplacement gas with liquefied gas being transferred.

19. Apparatus for dispensing gas material comprising the combinationwith a heat insulated container for holding a charge of liquefied gas atrelatively low. pressure, of a receiver for receiving gas material at arelatively high pressure, a transfer vessel interposed between and thereceiver arranged to receive successive portions of said charge when atlow pressure and to expel gas material to said receiver at relativelyhigh pressure, means for providing gas to effect such expulsion bydisplacement, means for withdrawing displacement said expulsion, meansfor cooling the withdrawn displacement gas by effector gas materialexpelled from the transfer vessel, means for additionally refrigerating.the withdrawn displacement gas by expansion, and means for admixing theexpanded displacement .gas with liquefied gas being transferred.

wmram F. MESINGER.

the containergas after it has effected l5. utilizing a refrigerating

